Handheld electronic devices, such as mobile phones, PDAs and digital cameras, typically include one display mechanism, such as an LCD or display window. The display mechanism can display files stored in the device, e.g., captured images, or a user interface, or other features, e.g., games, information, etc. The size of the display window is limited by the size of the device. Thus, as the size of a device gets smaller and smaller, so must the size of the display mechanism also get smaller.
Presently, the display window on handheld devices allow only one or two viewers to see the displayed contents comfortably. If more people wish to see, the display window must be placed farther from the viewers, which then makes it difficult, if not impossible, for each viewer to read words or to see details that are small.
Some handheld devices can be coupled via cables to a secondary display window that is external to the device, e.g., a television or projection system, such that the device transmits signals directly to the secondary display for group viewing. Many digital cameras support this feature. Other handheld devices include an integrated projection system, as described in U.S. Pat. No. 6,637,896, entitled “Compact Projection System and Associated Device,” issued to Li et al. on Oct. 28, 2003. In such a system, the device's projection system projects content onto a suitable surface, e.g., a flat wall or projection screen.
With each of the above described display mechanisms, the content displayed on the secondary display window mirrors that displayed on a primary display window, e.g., the LCD, on the device. Thus, if a user is displaying a presentation, the primary and secondary display windows include the content of the presentation, as well as control buttons and/or icons used by the presenter to manage the presentation. The user cannot control the content displayed on either the primary or secondary display mechanisms.
Accordingly, what is needed is an improved display mechanism for a handheld electronic device. The present invention addresses such a need.